# Observational signatures from horizonless black shells imitating rotating black holes

@article{Danielsson2018ObservationalSF, title={Observational signatures from horizonless black shells imitating rotating black holes}, author={Ulf H. Danielsson and Suvendu Giri}, journal={Journal of High Energy Physics}, year={2018}, volume={2018}, pages={1-24} }

A bstractIn arXiv:1705.10172 it was proposed that string theory replaces Schwarzschild black holes with horizonless thin shells with an AdS interior. In this paper we extend the analysis to slowly rotating black holes, solving the Israel-Lanczos-Sen junction conditions for a rotating shell composed of stringy matter to determine the metric. Outside of the shell we find a vacuum solution that differs from Kerr with a 32% larger quadrupole moment. We discuss the observational consequences and…

## 12 Citations

Reexamining the stability of rotating horizonless black shells mimicking Kerr black holes

- PhysicsPhysical Review D
- 2021

In arXiv:1705.10172 a string theory inspired alternative to gravitational collapse was proposed, consisting of a bubble of AdS space made up of ingredients from string theory. These ultra compact…

Re-examining the stability of rotating horizonless black shells mimicking Kerr black holes

- Physics
- 2021

In arXiv:1705.10172 a string theory inspired alternative to gravitational collapse was proposed, consisting of a bubble of AdS space made up of ingredients from string theory. These ultra compact…

Dynamics and observational signatures of shell-like black hole mimickers

- PhysicsPhysical Review D
- 2021

We undertake the task of studying the non-linear dynamics of quantum gravity motivated alternatives to black holes that in the classical limit appear as ultra-compact shells of matter. We develop a…

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- PhysicsLiving Reviews in Relativity
- 2019

Very compact objects probe extreme gravitational fields and may be the key to understand outstanding puzzles in fundamental physics. These include the nature of dark matter, the fate of spacetime…

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- PhysicsJournal of High Energy Physics
- 2021

Abstract
In this paper we study shells of matter and black holes on the expanding bubbles realizing de Sitter space, that were proposed in [4]. We construct explicit solutions for a rigid shell of…

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- PhysicsClassical and Quantum Gravity
- 2019

The grand challenges of contemporary fundamental physics—dark matter, dark energy, vacuum energy, inflation and early universe cosmology, singularities and the hierarchy problem—all involve gravity…

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- PhysicsJournal of High Energy Physics
- 2020

Motivated by the difficulty of constructing de Sitter vacua in string theory, a new approach was proposed in arXiv:1807.01570 and arXiv:1907.04268 , where four dimensional de Sitter space was…

Emergent de Sitter Cosmology from Decaying Anti-de Sitter Space.

- PhysicsPhysical review letters
- 2018

This work proposes an embedding of positive energy Friedmann-Lemaître-Robertson-Walker cosmology within string theory, confining 4D gravity on a brane which mediates the decay from a nonsupersymmetric five-dimensional anti-de Sitter false vacuum to a true vacuum.

De Sitter cosmology on an expanding bubble

- PhysicsJournal of High Energy Physics
- 2019

Abstract
Constructing an explicit compactification yielding a metastable de Sitter (dS) vacuum in a UV consistent string theory is an incredibly difficult open problem. Motivated by this issue, as…

UUITP-26 / 19 de Sitter Cosmology on an expanding bubble

- Physics
- 2019

Constructing an explicit compactification yielding a metastable de Sitter (dS) vacuum in a UV consistent string theory is an incredibly difficult open problem. Motivated by this issue, as well as the…

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